Abstract

Sonification is the process of representing data as non-speech audio signals. In this manuscript, we describe the auditory presentation of OCT data and images. OCT acquisition rates frequently exceed our ability to visually analyze image-based data, and multi-sensory input may therefore facilitate rapid interpretation. This conversion will be especially valuable in time-sensitive surgical or diagnostic procedures. In these scenarios, auditory feedback can complement visual data without requiring the surgeon to constantly monitor the screen, or provide additional feedback in non-imaging procedures such as guided needle biopsies which use only axial-scan data. In this paper we present techniques to translate OCT data and images into sound based on the spatial and spatial frequency properties of the OCT data. Results obtained from parameter-mapped sonification of human adipose and tumor tissues are presented, indicating that audio feedback of OCT data may be useful for the interpretation of OCT images.

Figures (6)

OCT image and data analysis from human breast (a) adipose tissue and (b) tumor tissue. (c) A-scan corresponding to the highlighted line from the adipose tissue. (d) A-scan corresponding to the highlighted line from the tumor tissue. (e) Normalized Fourier transforms (average of 150 A-scans). Roman numerals indicate the regions corresponding to the three spectral parameters. Scale bars represent 200 μm. The superimposed lines in (c) and (d) represent the 1st order fit to the A-scan for calculation of slope.

Sonification using the A-scan mode (Media 1 – both video and audio). (a) Human breast tissue containing a tumor margin with tumor (left side of the image) and adipose (right side of the image). (b) Audio spectrogram of the output sound, where each column in the spectrogram corresponds to 10 A-scans in the OCT image in (a).

Sonification using the image mode (Media 2 (13 MB) – both video and audio), (Media 3 (4 MB) – low display resolution video and audio). (a) A single frame from a three-dimensional volumetric data set, which consists of 450 frames played at 10 frames per second. (b) Audio spectrogram of the output sound where each frame in the three-dimensional volume now corresponds to a playback time of 100 ms, and the audio spectrum from each frame is represented by a single column in this spectrogram.